itech9

From http://www.perlmonks.org/?node_id=63955

How many ‘a’ characters are in the string?

#!/usr/bin/perl

my $str = 'abcatpdmeuziapmb';
my $cnt = @{[$str =~ /(a)/g]};
print “$cnt\n”;

#!/usr/bin/perl -w
use strict;

sub showHash($)
  {
    my(%hashh) = %{$_[0]};

    my($temp);
    foreach $temp (keys(%hashh)) { print “$temp=” . $hashh{$temp} . “\n”; }
    print “\n”;
  }

sub higherLevel($)
  {
    my(%hashh) = %{$_[0]};

    showHash(\%hashh);
  }

my %hash = (”1″=>”one”,”2″=>”two”,”3″=>”three”);

higherLevel(\%hash);

From http://www.cs.cf.ac.uk/Dave/PERL/node61.html ..

@array1  = (1..5);
@array2  = ("A".."E");

firstSub( \@array1,  \@array2);         # One

sub firstSub {
    my($ref_firstArray, $ref_secondArray) = @_;   # Two

    print("The first array is  @{$ref_firstArray}.\n");  # Three

    print("The second array is @{$ref_secondArray}.\n"); # Three

}

#!/usr/bin/perl

use strict;

{ package SomeClass;

  sub new {
    my $class = shift;
    my $self = {
	v1 => undef,
	v2 => undef,
    };
    bless($self, $class);
    return $self;
  }

  sub setV1($) {
    my $self = shift;
    if (@_) {
      $self->{v1} = shift
    }
    return $self->{v1};
  }

  sub getV1() {
    my $self = shift;
    return $self->{v1};
  }
}

main();

sub main() {
  my $foo = SomeClass->new();
  $foo->setV1(38);
  print $foo->getV1() . "\n";
}

From http://goldenink.com/perl/perldebug.html

perl -w myprogram

perl -d myprogram

* c (continue) - start program (or continue from breakpoint)
* l - lists the next few lines
* p [variable name] - print the value of a variable
* q - quit.
* r - returns from current subroutine
* n - executes the next statement at this level
* s - The step command - just hit enter to repeat the command.
* b - Set a breakpoint - “b n” for line “n”, see other conditional breakpoints.